1. Field of the Invention
The present invention relates to aldehyde functional group containing polymers and to a method for producing the aldehyde functional group containing polymers having a molecular weight of about 500 to 50,000 and containing aldehyde functional groups at both ends and/or on the side chains of the molecule.
2. Description of the Prior Art
Various methods are known for producing functional polymers having functional groups at both ends and/or on the side chains of the molecule.
For example, polymerizable monomers are subjected to a living polymerization to introduce hydroxyl groups, carboxyl groups, thioalcohol groups and the like into ends of the living polymer, whereby polymers having functional groups at both ends of the molecule are obtained.
On the other hand, methods for producing functional polymers having carboxyl groups or hydroxyl groups at ends of the molecule in which a high polymer having olefinically unsaturated double bonds is reacted with ozone to effect ozone-decomposition of some of the double bonds contained in the high polymer and then the resulting ozone-decomposition products are oxidized or reduced, have been disclosed in U.S. Pat. No. 3,392,154 and British Pat. No. 984,071.
However, no method for producing polymers having only aldehyde functional groups at both ends and/or on the side chains of the polymer molecule is known.
This is because the aldehyde group itself is very unstable and U.S. Pat. No. 3,392,154 for example, has suggested that an aldehyde functional polymer is produced as a reaction intermediate but thereafter this polymer is converted into a carboxyl functional polymer or a hydroxyl functional polymer and it is impossible to recover the aldehyde functional polymer per se.
An object of the present invention is to provide polymers having substantially only aldehyde functional groups at both ends and/or on the side chains of the molecule as the functional group and the present invention has succeeded in the production of aldehyde functional polymers from ozone-decomposition products of high polymers having olefinically unsaturated double bonds after a large number of experiments and studies have been made.